U.S. patent application number 14/904746 was filed with the patent office on 2016-06-09 for priming configuration for a medical device and drug delivery device comprising a priming configuration.
The applicant listed for this patent is SANOFI. Invention is credited to Stuart Milne, Tom Oakley, Matt Schumann.
Application Number | 20160158451 14/904746 |
Document ID | / |
Family ID | 48803409 |
Filed Date | 2016-06-09 |
United States Patent
Application |
20160158451 |
Kind Code |
A1 |
Oakley; Tom ; et
al. |
June 9, 2016 |
PRIMING CONFIGURATION FOR A MEDICAL DEVICE AND DRUG DELIVERY DEVICE
COMPRISING A PRIMING CONFIGURATION
Abstract
The priming configuration comprises a piston rod (1), a bung
(2), which is provided to be driven by the piston rod, and a
movable element (5), which is engaged with the piston rod. The
movable element is arranged to be movable in a predefined direction
(10) with respect to the piston rod by a user of the drug delivery
device. A movement of the movable element in the predefined
direction advances the piston rod in a further direction (11),
providing a priming of the drug delivery device before use. The
predefined direction may especially be transverse to the further
direction, and the further direction may especially be directed
from the piston rod towards the bung (2). A gap (12) or clearance
between the piston rod (1) and the bung (2) can thus be removed,
and the stiction of the bung (2) to the cartridge (3) can be
reduced.
Inventors: |
Oakley; Tom; (Cambridge
Cambridgeshire, GB) ; Schumann; Matt; (Bourn,
Cambridge, Cambridgeshire, GB) ; Milne; Stuart;
(Buckden St. Neots, Cambridgeshire, GB) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SANOFI |
Paris |
|
FR |
|
|
Family ID: |
48803409 |
Appl. No.: |
14/904746 |
Filed: |
July 17, 2014 |
PCT Filed: |
July 17, 2014 |
PCT NO: |
PCT/EP2014/065333 |
371 Date: |
January 13, 2016 |
Current U.S.
Class: |
128/200.23 ;
604/207 |
Current CPC
Class: |
A61M 5/3146 20130101;
A61M 2005/1402 20130101; A61M 11/007 20140204; A61M 5/31515
20130101; A61M 15/009 20130101; A61M 5/31511 20130101; A61M 5/1452
20130101; A61M 5/31583 20130101 |
International
Class: |
A61M 5/31 20060101
A61M005/31; A61M 11/00 20060101 A61M011/00 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 17, 2013 |
EP |
13176858.2 |
Claims
1. A priming configuration for a medical device, comprising: a
movable functional part (1) provided for an operation of the
device, and a movable element (5) operationally coupled with the
functional part (1), characterized in that the movable element (5)
is arranged to be movable in a predefined direction (10) with
respect to the functional part (1) by a user of the medical device,
a movement of the movable element (5) in the predefined direction
(10) advancing the functional part (1) in a further direction (11)
thereby providing a priming of the medical device before use.
2. The priming configuration of claim 1, wherein the priming
configuration is a piston rod arrangement for priming a drug
delivery device, and the movable functional part (1) is a piston
rod (1).
3. The priming configuration of claim 1 or 2, wherein the
functional part (1) is a piston rod (1), and the piston rod (1) is
provided to drive a bung (2) of a container (3) containing a drug
in a drug delivery device.
4. The priming configuration of claim 3, wherein the priming
includes a slight movement of the bung (2) generated by the movable
element (5) to overcome a stiction of the bung (2) to the container
(3).
5. The priming configuration of claim 3 or 4, further comprising: a
spring provided to move the bung (2), the spring advancing the
piston rod (1) in the further direction (11) thereby providing the
priming.
6. The priming configuration according to one of claims 3 to 5,
wherein the predefined direction (10) is transverse to the further
direction (11), and the further direction (11) is from the piston
rod (1) towards the bung (2).
7. The priming configuration according to one of claims 2 to 6,
wherein the movable element (5) is operationally coupled with the
piston rod (1) by an inclined surface (8) of the movable element
(5), the inclined surface (8) being inclined with respect to the
further direction (11) and being in contact with the piston rod
(1).
8. The priming configuration according to one of claims 2 to 7,
further comprising: an opening (6) in the piston rod (1), the
movable element (5) extending into the opening (6) and being
engaged with the piston rod (1) within the opening (6).
9. The priming configuration according to one of claims 2 to 8,
further comprising: a grip (7) of the movable element (5), the grip
(7) being provided to move the movable element (5) in the
predefined direction (10), and wherein the predefined direction is
a direction away from the piston rod (1).
10. The priming configuration according to one of claims 2 to 9,
further comprising: a button (9) of the movable element (5), the
button (9) being provided to move the movable element (5) in the
predefined direction (10), and wherein the predefined direction is
a direction towards the piston rod (1).
11. The priming configuration according to one of claims 2 to 10,
wherein the movable element (5) is provided to be removed from the
piston rod (1).
12. The priming configuration of claim 1, wherein the functional
part (1) is in communication with a mechanical pump.
13. The priming configuration of claim 1, wherein the functional
part (1) is in communication with a metering chamber.
14. A drug delivery device comprising a priming configuration
according to one of claims 1 to 13.
15. The drug delivery device of claim 14, the drug delivery device
being an injection device.
16. The drug delivery device of claim 14 or 15, the drug delivery
device being a pen-type device.
Description
[0001] Drug delivery devices, in particular pen-type injection
devices, comprise a bung, which serves to eject doses of a drug
from a container and may be provided as part of a drug cartridge,
and a piston rod driving the bung. The piston rod may be provided
with a bearing to facilitate a relative movement of the piston rod
with respect to the bung. The drug delivery device may be provided
with a mechanism for setting a dose and for advancing the piston
rod to deliver the dose set.
[0002] At the end of the assembly of the device a gap may
intentionally be left between the end of the piston rod and the
bung. The gap is a consequence of the tolerances associated with
the assembled parts and of the desire not to pre-load the bung in
the assembled device before the first usage takes place.
[0003] When the device is used for the first time, the dose
actually delivered is liable to be less than the dose set, and the
difference equals the volume that would be ejected if the bung were
travelling simultaneously with the piston rod even before the
piston rod gets into contact with the bung. This may cause the
first dose to be well outside the allowable accuracy limits.
[0004] The user is therefore instructed to perform a priming step
like the ejection of `air shot` prime doses until fluid begins to
be ejected. Priming is such an act of preparing the device for
first use. Except for a removal of any clearances and tolerances in
the device, priming may be required to overcome a static friction
or `stiction` of parts occurring when the device has not been used
for some time, in particular for the time between manufacture and
first use. The bung tends to stick to the cartridge, for instance,
and moving the bung for the first time usually requires a greater
force than on subsequent shots.
[0005] Sub-lingual spray devices are sometimes based on mechanical
pumps which aerosolise a liquid medicament. The pump needs to be
primed before use to ensure that the metering chamber is full.
[0006] Metered dose inhalers typically feature a metering chamber
which may contain fluid (liquid, possibly with suspended particles,
or gas, or a mixture of said liquids and gases). The fluid may be
at the same pressure as ambient pressure or different. It is
sometimes advantageous to prime the metered dose inhaler such that
the metering chamber contains an acceptable mass of an acceptable
fluid or mixture of fluids, and at an acceptable pressure for
subsequent use in drug delivery.
[0007] It is an object of the present invention to provide an easy
way of priming a medical device, in particular a drug delivery
device comprising a piston rod that is provided to drive a bung for
expelling a drug from a container like a cartridge.
[0008] This object is achieved with the priming configuration
according to claim 1 and with the drug delivery device according to
claim 14. Further embodiments and variants derive from the
dependent claims.
[0009] A piston rod according to this invention shall mean any
member that is intended to drive a piston or bung of a drug
delivery device and may particularly be a lead screw.
[0010] The term "drug", as used herein, preferably means a
pharmaceutical formulation containing at least one pharmaceutically
active compound, wherein in one embodiment the pharmaceutically
active compound has a molecular weight up to 1500 Da and/or is a
peptide, a proteine, a polysaccharide, a vaccine, a DNA, a RNA, an
enzyme, an antibody or a fragment thereof, a hormone or an
oligonucleotide, or a mixture of the above-mentioned
pharmaceutically active compound,
wherein in a further embodiment the pharmaceutically active
compound is useful for the treatment and/or prophylaxis of diabetes
mellitus or complications associated with diabetes mellitus such as
diabetic retinopathy, thromboembolism disorders such as deep vein
or pulmonary thromboembolism, acute coronary syndrome (ACS),
angina, myocardial infarction, cancer, macular degeneration,
inflammation, hay fever, atherosclerosis and/or rheumatoid
arthritis, wherein in a further embodiment the pharmaceutically
active compound comprises at least one peptide for the treatment
and/or prophylaxis of diabetes mellitus or complications associated
with diabetes mellitus such as diabetic retinopathy, wherein in a
further embodiment the pharmaceutically active compound comprises
at least one human insulin or a human insulin analogue or
derivative, glucagon-like peptide (GLP-1) or an analogue or
derivative thereof, or exendin-3 or exendin-4 or an analogue or
derivative of exendin-3 or exendin-4.
[0011] Insulin analogues are for example Gly(A21), Arg(B31),
Arg(B32) human insulin; Lys(B3), Glu(B29) human insulin; Lys(B28),
Pro(B29) human insulin; Asp(B28) human insulin; human insulin,
wherein proline in position B28 is replaced by Asp, Lys, Leu, Val
or Ala and wherein in position B29 Lys may be replaced by Pro;
Ala(B26) human insulin; Des(B28-B30) human insulin; Des(B27) human
insulin and Des(B30) human insulin.
[0012] Insulin derivates are for example B29-N-myristoyl-des(B30)
human insulin; B29-N-palmitoyl-des(B30) human insulin;
B29-N-myristoyl human insulin; B29-N-palmitoyl human insulin;
B28-N-myristoyl LysB28ProB29 human insulin;
B28-N-palmitoyl-LysB28ProB29 human insulin;
B30-N-myristoyl-ThrB29LysB30 human insulin;
B30-N-palmitoyl-ThrB29LysB30 human insulin;
B29-N--(N-palmitoyl-Y-glutamyl)-des(B30) human insulin;
B29-N--(N-lithocholyl-Y-glutamyl)-des(B30) human insulin;
B29-N-(.omega.-carboxyheptadecanoyl)-des(B30) human insulin and
B29-N-(.omega.-carboxyheptadecanoyl) human insulin.
[0013] Exendin-4 for example means Exendin-4(1-39), a peptide of
the sequence
H-His-Gly-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Leu-Ser-Lys-Gln-Met-Glu-Gl-
u-Glu-Ala-Val-Arg-Leu-Phe-Ile-Glu-Trp-Leu-Lys-Asn-Gly-Gly-Pro-Ser-Ser-Gly--
Ala-Pro-Pro-Pro-Ser-NH2.
[0014] Exendin-4 derivatives are for example selected from the
following list of compounds:
H-(Lys)4-des Pro36, des Pro37 Exendin-4(1-39)-NH2,
H-(Lys)5-des Pro36, des Pro37 Exendin-4(1-39)-NH2,
des Pro36 Exendin-4(1-39),
des Pro36 [Asp28] Exendin-4(1-39),
des Pro36 [IsoAsp28] Exendin-4(1-39),
des Pro36 [Met(O)14, Asp28] Exendin-4(1-39),
des Pro36 [Met(O)14, IsoAsp28] Exendin-4(1-39),
des Pro36 [Trp(O2)25, Asp28] Exendin-4(1-39),
des Pro36 [Trp(O2)25, IsoAsp28] Exendin-4(1-39),
des Pro36 [Met(O)14 Trp(O2)25, Asp28] Exendin-4(1-39),
des Pro36 [Met(O)14 Trp(O2)25, IsoAsp28] Exendin-4(1-39); or
des Pro36 [Asp28] Exendin-4(1-39),
des Pro36 [IsoAsp28] Exendin-4(1-39),
des Pro36 [Met(O)14, Asp28] Exendin-4(1-39),
des Pro36 [Met(O)14, IsoAsp28] Exendin-4(1-39),
des Pro36 [Trp(O2)25, Asp28] Exendin-4(1-39),
des Pro36 [Trp(O2)25, IsoAsp28] Exendin-4(1-39),
des Pro36 [Met(O)14 Trp(O2)25, Asp28] Exendin-4(1-39),
des Pro36 [Met(O)14 Trp(O2)25, IsoAsp28] Exendin-4(1-39),
[0015] wherein the group -Lys6-NH2 may be bound to the C-terminus
of the Exendin-4 derivative; or an Exendin-4 derivative of the
sequence
des Pro36 Exendin-4(1-39)-Lys6-NH2 (AVE0010),
H-(Lys)6-des Pro36 [Asp28] Exendin-4(1-39)-Lys6-NH2,
des Asp28 Pro36, Pro37, Pro38Exendin-4(1-39)-NH2,
H-(Lys)6-des Pro36, Pro38 [Asp28] Exendin-4(1-39)-NH2,
H-Asn-(Glu)5des Pro36, Pro37, Pro38 [Asp28]
Exendin-4(1-39)-NH2,
des Pro36, Pro37, Pro38 [Asp28] Exendin-4(1-39)-(Lys)6-NH2,
H-(Lys)6-des Pro36, Pro37, Pro38 [Asp28]
Exendin-4(1-39)-(Lys)6-NH2,
H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Asp28]
Exendin-4(1-39)-(Lys)6-NH2,
H-(Lys)6-des Pro36 [Trp(O2)25, Asp28] Exendin-4(1-39)-Lys6-NH2,
H-des Asp28 Pro36, Pro37, Pro38 [Trp(O2)25]
Exendin-4(1-39)-NH2,
H-(Lys)6-des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28]
Exendin-4(1-39)-NH2,
H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28]
Exendin-4(1-39)-NH2,
des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28]
Exendin-4(1-39)-(Lys)6-NH2,
H-(Lys)6-des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28]
Exendin-4(1-39)-(Lys)6-NH2,
H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Trp(O2)25, Asp28]
Exendin-4(1-39)-(Lys)6-NH2,
H-(Lys)6-des Pro36 [Met(O)14, Asp28] Exendin-4(1-39)-Lys6-NH2,
des Met(O)14 Asp28 Pro36, Pro37, Pro38 Exendin-4(1-39)-NH2,
H-(Lys)6-desPro36, Pro37, Pro38 [Met(O)14, Asp28]
Exendin-4(1-39)-NH2,
H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Met(O)14, Asp28]
Exendin-4(1-39)-NH2,
des Pro36, Pro37, Pro38 [Met(O)14, Asp28]
Exendin-4(1-39)-(Lys)6-NH2,
H-(Lys)6-des Pro36, Pro37, Pro38 [Met(O)14, Asp28]
Exendin-4(1-39)-(Lys)6-NH2,
H-Asn-(Glu)5 des Pro36, Pro37, Pro38 [Met(O)14, Asp28]
Exendin-4(1-39)-(Lys)6-NH2,
H-Lys6-des Pro36 [Met(O)14, Trp(O2)25, Asp28]
Exendin-4(1-39)-Lys6-NH2,
H-des Asp28 Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25]
Exendin-4(1-39)-NH2,
H-(Lys)6-des Pro36, Pro37, Pro38 [Met(O)14, Asp28]
Exendin-4(1-39)-NH2,
H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25, Asp28]
Exendin-4(1-39)-NH2,
des Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25, Asp28]
Exendin-4(1-39)-(Lys)6-NH2,
H-(Lys)6-des Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25, Asp28]
Exendin-4(S1-39)-(Lys)6-NH2,
H-Asn-(Glu)5-des Pro36, Pro37, Pro38 [Met(O)14, Trp(O2)25, Asp28]
Exendin-4(1-39)-(Lys)6-NH2;
[0016] or a pharmaceutically acceptable salt or solvate of any one
of the afore-mentioned Exendin-4 derivative.
[0017] Hormones are for example hypophysis hormones or hypothalamus
hormones or regulatory active peptides and their antagonists as
listed in Rote Liste, ed. 2008, Chapter 50, such as Gonadotropine
(Follitropin, Lutropin, Choriongonadotropin, Menotropin),
Somatropine (Somatropin), Desmopressin, Terlipressin, Gonadorelin,
Triptorelin, Leuprorelin, Buserelin, Nafarelin, Goserelin.
[0018] A polysaccharide is for example a glucosaminoglycane, a
hyaluronic acid, a heparin, a low molecular weight heparin or an
ultra low molecular weight heparin or a derivative thereof, or a
sulphated, e.g. a poly-sulphated form of the above-mentioned
polysaccharides, and/or a pharmaceutically acceptable salt thereof.
An example of a pharmaceutically acceptable salt of a
poly-sulphated low molecular weight heparin is enoxaparin
sodium.
[0019] Antibodies are globular plasma proteins (.about.150 kDa)
that are also known as immunoglobulins which share a basic
structure. As they have sugar chains added to amino acid residues,
they are glycoproteins. The basic functional unit of each antibody
is an immunoglobulin (Ig) monomer (containing only one Ig unit);
secreted antibodies can also be dimeric with two Ig units as with
IgA, tetrameric with four Ig units like teleost fish IgM, or
pentameric with five Ig units, like mammalian IgM.
[0020] The Ig monomer is a "Y"-shaped molecule that consists of
four polypeptide chains; two identical heavy chains and two
identical light chains connected by disulfide bonds between
cysteine residues. Each heavy chain is about 440 amino acids long;
each light chain is about 220 amino acids long. Heavy and light
chains each contain intrachain disulfide bonds which stabilize
their folding. Each chain is composed of structural domains called
Ig domains. These domains contain about 70-110 amino acids and are
classified into different categories (for example, variable or V,
and constant or C) according to their size and function. They have
a characteristic immunoglobulin fold in which two .beta. sheets
create a "sandwich" shape, held together by interactions between
conserved cysteines and other charged amino acids.
[0021] There are five types of mammalian Ig heavy chain denoted by
.alpha., .delta., .epsilon., .gamma., and .mu.. The type of heavy
chain present defines the isotype of antibody; these chains are
found in IgA, IgD, IgE, IgG, and IgM antibodies, respectively.
[0022] Distinct heavy chains differ in size and composition;
.alpha. and .gamma. contain approximately 450 amino acids and
.delta. approximately 500 amino acids, while .mu. and .epsilon.
have approximately 550 amino acids. Each heavy chain has two
regions, the constant region (C.sub.H) and the variable region
(V.sub.H). In one species, the constant region is essentially
identical in all antibodies of the same isotype, but differs in
antibodies of different isotypes. Heavy chains .gamma., .alpha. and
.delta. have a constant region composed of three tandem Ig domains,
and a hinge region for added flexibility; heavy chains .mu. and
.epsilon. have a constant region composed of four immunoglobulin
domains. The variable region of the heavy chain differs in
antibodies produced by different B cells, but is the same for all
antibodies produced by a single B cell or B cell clone. The
variable region of each heavy chain is approximately 110 amino
acids long and is composed of a single Ig domain.
[0023] In mammals, there are two types of immunoglobulin light
chain denoted by A and K. A light chain has two successive domains:
one constant domain (CL) and one variable domain (VL). The
approximate length of a light chain is 211 to 217 amino acids. Each
antibody contains two light chains that are always identical; only
one type of light chain, .kappa. or .lamda., is present per
antibody in mammals.
[0024] Although the general structure of all antibodies is very
similar, the unique property of a given antibody is determined by
the variable (V) regions, as detailed above. More specifically,
variable loops, three each the light (VL) and three on the heavy
(VH) chain, are responsible for binding to the antigen, i.e. for
its antigen specificity. These loops are referred to as the
Complementarity Determining Regions (CDRs). Because CDRs from both
VH and VL domains contribute to the antigen-binding site, it is the
combination of the heavy and the light chains, and not either
alone, that determines the final antigen specificity.
[0025] An "antibody fragment" contains at least one antigen binding
fragment as defined above, and exhibits essentially the same
function and specificity as the complete antibody of which the
fragment is derived from. Limited proteolytic digestion with papain
cleaves the Ig prototype into three fragments. Two identical amino
terminal fragments, each containing one entire L chain and about
half an H chain, are the antigen binding fragments (Fab). The third
fragment, similar in size but containing the carboxyl terminal half
of both heavy chains with their interchain disulfide bond, is the
crystalizable fragment (Fc). The Fc contains carbohydrates,
complement-binding, and FcR-binding sites. Limited pepsin digestion
yields a single F(ab')2 fragment containing both Fab pieces and the
hinge region, including the H--H interchain disulfide bond. F(ab')2
is divalent for antigen binding. The disulfide bond of F(ab')2 may
be cleaved in order to obtain Fab'. Moreover, the variable regions
of the heavy and light chains can be fused together to form a
single chain variable fragment (scFv).
[0026] Pharmaceutically acceptable salts are for example acid
addition salts and basic salts. Acid addition salts are e.g. HCl or
HBr salts. Basic salts are e.g. salts having a cation selected from
alkali or alkaline, e.g. Na+, or K+, or Ca2+, or an ammonium ion
N+(R1)(R2)(R3)(R4), wherein R1 to R4 independently of each other
mean: hydrogen, an optionally substituted C1-C6-alkyl group, an
optionally substituted C2-C6-alkenyl group, an optionally
substituted C6-C10-aryl group, or an optionally substituted
C6-C10-heteroaryl group. Further examples of pharmaceutically
acceptable salts are described in "Remington's Pharmaceutical
Sciences" 17. ed. Alfonso R. Gennaro (Ed.), Mark Publishing
Company, Easton, Pa., U.S.A., 1985 and in Encyclopedia of
Pharmaceutical Technology.
[0027] Pharmaceutically acceptable solvates are for example
hydrates.
[0028] The priming configuration comprises a movable functional
part provided for an operation of the device, and a movable element
or exerciser operationally coupled with the functional part. The
movable element is arranged to be movable in a predefined direction
with respect to the functional part by a user of the medical
device, a movement of the movable element in the predefined
direction advancing the functional part in a further direction
thereby providing a priming of the medical device before use.
[0029] The priming may be any operation putting the device in
condition for ready use. It may especially comprise a removal of
any clearances or tolerances between parts of the device and may be
adapted to put components of the device into suitable compression
or tension, for example. It may also comprise a movement of a
mechanical part to overcome a stiction caused when the device is
not used for a significant period of time, particularly between
manufacture and first use. It may also comprise the removal of gas
such as air from the drug container and/or needle. It may also
comprise the ejection of drug from the device.
[0030] The priming configuration may be used in a variety of
medical devices, including drug delivery devices or sub-lingual
spray devices or metered dose inhalers, for instance. The priming
configuration of a drug delivery device especially comprises a
movable element or exerciser, which allows the drug delivery device
to be completely and reliably primed for first use in one easy step
of operation. The movable element serves to generate a slight
movement of the piston rod in the direction towards the bung to
take up any manufacturing tolerances. Instead or additionally, the
movable element may generate a slight movement of the bung to
overcome the stiction from long-term storage. Instead or
additionally, the movable element may change the mass or mixture of
fluids in a metering chamber, or change the pressure in a metering
chamber. The movable element may especially be a removable element,
which is removed from the device after the priming step. In
particular, the priming configuration may be a piston rod
arrangement for priming a drug delivery device, and the movable
functional part may be a piston rod.
[0031] The priming configuration is especially advantageous in drug
delivery devices using a spring to move the bung. The spring must
otherwise provide enough force or torque to overcome the initial
stiction force, even when the user sets only the minimum dose.
Therefore the spring has to provide greater force and/or torque
than would be necessary if it did not have to overcome the
stiction. Therefore, one or more components may be subjected to
greater force and/or torque, which may require materials and/or
component design to avoid failures due to deflection, yield, creep
or fatigue. This results in larger size and larger mass of the
device and increases the device cost. Furthermore the user has to
apply a greater torque when selecting a dose. In spring-driven drug
delivery devices the priming configuration allows the application
of a weaker and smaller driving spring.
[0032] In one aspect the invention relates to a priming
configuration for a drug delivery device, comprising a piston rod,
a bung, which is provided to be driven by the piston rod, and a
movable element, which is engaged with the piston rod. The movable
element is arranged to be movable in a predefined direction with
respect to the piston rod by a user of the drug delivery device. A
movement of the movable element in the predefined direction
advances the piston rod in a further direction. The predefined
direction may especially be transverse to the further direction,
and the further direction may especially be directed from the
piston rod towards the bung. The advancement of the piston rod does
not belong to the regular use of the device and is not intended for
selecting or delivering a dose, but only provides a priming of the
drug delivery device before use.
[0033] In an embodiment of the priming configuration the movable
element is engaged with the piston rod by making a contact with the
piston rod in an inclined surface of the movable element. The
inclined surface is inclined with respect to the further direction
and is in contact with the piston rod. This has the advantage of an
easy construction, because the arrangement of the contact surface
between the piston rod and the movable element suffices to advance
the piston rod by a movement of the movable element.
[0034] A further embodiment of the priming configuration further
comprises an opening in the piston rod, the movable element
extending into the opening and being engaged with the piston rod
within the opening. This has the advantage that the operational
coupling with the movable element may be arranged at the axial
centre of the piston rod and at various positions along the piston
rod.
[0035] A further embodiment of the priming configuration further
comprises a grip of the movable element, the grip being provided to
move the movable element in the predefined direction away from the
piston rod. This has the advantage that the movable element may
thus be removed from the device.
[0036] A further embodiment of the priming configuration further
comprises a button of the movable element, the button being
provided to move the movable element in the predefined direction
towards the piston rod. This has the advantage that the movable
element may be provided as an operation button on the device.
[0037] The movable element may be provided to be removed from the
piston rod, especially to be completely removed from the drug
delivery device. This has the advantage that the movable element,
which is only used once, does not interfere with the further use of
the device and that it may be seen from the outer appearance of the
device whether the priming step has already been performed.
[0038] In a further embodiment of the priming configuration, the
functional part is in communication with a mechanical pump.
[0039] In a further embodiment of the priming configuration, the
functional part is in communication with a metering chamber.
[0040] In another aspect the invention relates to a drug delivery
device comprising such a priming configuration. The drug delivery
device may especially be an injection device and/or a pen-type
device. The priming configuration is especially suitable for drug
delivery devices, because it allows easy manufacture of the device
and easy priming to remove any manufacturing tolerances.
[0041] The following is a detailed description of embodiments of
the priming configuration in conjunction with the appended
drawings.
[0042] FIG. 1 is a cross section of an embodiment of the priming
configuration.
[0043] FIG. 2 is a cross section of a further embodiment of the
priming configuration.
[0044] FIG. 1 is a cross section of an embodiment of the priming
configuration in which the movable element or exerciser is
implemented as a `pull-tab`. The piston rod 1 may already be in
contact with the bung 2, or the piston rod 1 may instead be
arranged at a very small distance from the bung 2, as shown in the
example of FIG. 1. The bung 2 may be provided in a cartridge 3,
which contains a drug. The cartridge 3 may be inserted in a body 4
or housing of a drug delivery device. Instead of a cartridge 3, any
drug container or receptacle may be provided, and the bung 2 may be
arranged within the container at a position suitable for expelling
the drug. The small gap 12 between the piston rod 1 and the bung 2
may be a clearance that is due to assembly tolerances or the like.
This gap 12 is to be removed by a priming step, and a possible
stiction of the bung 2 at the inner side walls of the cartridge 3
or container is to be overcome. The movable element 5 is engaged
with the piston rod 1 and is provided with some kind of operation
element like a tab or grip 7, which may be arranged, in particular
at or near a surface of a body 4 or extending out of a body 4, in
such a fashion that a user can pull the movable element 5 in the
predefined direction 10 away from the piston rod 1. The act of
pulling the tab or grip 7 moves the piston rod 1 in the further
direction 11 into contact with the bung 2, thus removing the
clearance due to manufacturing tolerances. The movement of the
piston rod 1 may be continued to reduce the stiction of the bung 2
by a slight movement of the bung 2 relative to the cartridge 3 or
container. The movement of the piston rod 1 may be continued to
expel some or all gas from the drug container 3 and/or needle (not
shown). The movement of the piston rod 1 may be continued to expel
some drug from the drug delivery device.
[0045] The transmission of the movement of the movable element 5
into a movement of the piston rod 1 may be effected by an inclined
surface 8 of the movable element 5 engaging the piston rod 1. In
the embodiment according to FIG. 1, the movable element 5 extends
into an opening 6 of the piston rod 1, and the inclined surface 8
is in contact with the piston rod 1 within the opening 6. The
inclined surface 8 may be formed by a widening of the part of the
movable element 5 that extends into the opening 6. When the movable
element 5 is pulled in the predefined direction 10 the inclined
surface 8 slides on an inner rim of the opening 6 and pushes the
piston rod 1 in the further direction 11 towards the bung 2. In
this case the predefined direction 10 is essentially transverse to
the further direction 11. The movable element 5 may be intended to
be left in the device after priming, and in this case it may be
formed as a feature created from the body 4 or another component of
the device. The movable element 5 may instead be intended to be
completely removed from the device in the course of the priming
step.
[0046] FIG. 2 is a cross section of a further embodiment of the
priming configuration in which the movable element or exerciser is
implemented as a button. The elements of the embodiment according
to FIG. 2 that are similar to elements of the embodiment according
to FIG. 1 are designated with the same reference numerals. The
movable element 5 comprising the button 9 may be formed as a
separate component of the device, or it may be a feature created
from the body 4 or another component. In order to prime the device
the user presses the button 9 to push the movable element 5 in the
predefined direction 10, which is towards the piston rod 1 in this
embodiment. The act of pressing the button 9 moves the piston rod 1
in the further direction 11 into contact with the bung 2, and the
bung 2 may also be moved slightly relative to the cartridge 3 or
container to reduce the stiction of the bung 2. The movement of the
piston rod 1 may be continued to expel some or all gas from the
drug container 3 and/or needle (not shown). The movement of the
piston rod 1 may be continued to expel some drug from the drug
delivery device.
[0047] The transmission of the movement of the movable element 5
into a movement of the piston rod 1 may be effected by an inclined
surface 8 of the movable element 5 engaging the piston rod 1 in a
way similar to the embodiment according to FIG. 1. In the
embodiment according to FIG. 2 the movable element 5 also extends
into an opening 6 of the piston rod 1, and the inclined surface 8,
which may be formed by a tapering of the movable element 5, is in
contact with the piston rod 1 within the opening 6. When the
movable element 5 is pushed in the predefined direction 10 the
inclined surface 8 slides on an inner rim of the opening 6 and
pushes the piston rod 1 in the further direction 11 towards the
bung 2. In this case the predefined direction 10 is also
essentially transverse to the further direction 11. The movable
element 5 may be intended to be removed from the device after
priming, in order to offer a free passage to the piston rod 1. To
this end the button 9 may be formed in such a manner that it can be
gripped to pull the movable element 5 out of the body 4.
Alternatively, the movable element 5 may remain in the device but
be implemented in such a way as not to impede the subsequent
function of the piston rod 1.
[0048] In other embodiments of the priming configuration, the
functional part may be in communication with a mechanical pump or
with a metering chamber.
[0049] The priming configuration has especially the advantages that
it reduces the number of user steps to one push or pull and, in
addition, guarantees that the user performs the priming correctly.
Another advantage is that it may be made apparent to the user(s)
whether or not priming has been performed. A wastage of drug
formulation is avoided during priming. Stiction of the bung is
effectively reduced. The described priming exerciser is useful in
all known designs of drug delivery devices, especially pen-type
devices. It may also be applied in sub-lingual spray devices that
comprise a mechanical pump rendering an aerosol of a liquid
medicament. The pump needs to be primed before use to ensure that
the metering chamber is full. It may also be applied to metered
dose inhalers that comprise a metering chamber. The priming
configuration can be used to ensure that an acceptable mass of an
acceptable fluid or mixture of fluids is in the metering chamber
and at an acceptable pressure.
REFERENCE NUMERALS
[0050] 1 piston rod [0051] 2 bung [0052] 3 cartridge [0053] 4 body
[0054] 5 movable element [0055] 6 opening [0056] 7 grip [0057] 8
inclined surface [0058] 9 button [0059] 10 direction [0060] 11
further direction [0061] 12 gap
* * * * *